Server authentication

Abstract

A method of authenticating a content-provider server, the method comprising: determining a domain name of the content-provider server; obtaining a fragment of a database of IP addresses, the fragment corresponding to the domain name of the content-provider server and storing one or more IP addresses associated with the domain name; comparing the IP address of the content-provider server against the IP addresses of the fragment; and providing an indication that the IP address of the content-provider server is included or excluded from the fragment of IP addresses. Additionally, a client computer and server operable to implement the method are described.

1 - 39 . (canceled) 
   
   
       40 . A method of authenticating a content-provider server having an IP address, the method comprising:
 determining a domain name of the content-provider server;   obtaining a fragment of a database of IP addresses, the fragment corresponding to the domain name of the content-provider server and storing one or more IP addresses associated with the domain name;   comparing the IP address of the content-provider server against the IP addresses of the fragment; and   providing an indication that the IP address of the content-provider server is included or excluded from the fragment of IP addresses.   
   
   
       41 . A method according to  claim 40 , wherein the fragment is stored on a remote server and obtaining the fragment comprises requesting from the remote server a copy of the fragment and receiving from the remote server a copy of the fragment. 
   
   
       42 . A method according to  claim 41 , wherein the fragment is stored on the remote server as a file having a filename that is unique to the domain name of the content-provider server and requesting a copy of the fragment from the remote server comprises requesting a file having a filename that is unique to the domain name of the content-provider server. 
   
   
       43 . A method according to  claim 42 , wherein the filename of the fragment is unique to both the domain name of the content-provider server and a domain name of the remote server on which the fragment is stored. 
   
   
       44 . A method according to  claim 43 , wherein the filename of the fragment is encrypted using encryption keys derived from the domain name of the content-provider server and the domain name of the remote server on which the fragment is stored. 
   
   
       45 . A method according to  claim 40 , wherein the fragment stores one or more authenticated IP addresses and one or more non-authenticated IP addresses and the method comprises providing an indication that the IP address of the content-provider server is an authenticated IP address, a non-authenticated IP address, or neither. 
   
   
       46 . A method according to  claim 45 , wherein the method comprises:
 storing a database of authenticated IP addresses and a database of non-authenticated IP addresses;   appending the IP addresses of the fragment to at least one of the database of authenticated IP addresses and the database of non-authenticated IP addresses;   comparing the IP address of the content-provider server against the database of authenticated IP addresses and the database of non-authenticated IP addresses; and   providing an indication that the IP address of the content-provider server is an authenticated IP address, a non-authenticated IP address, or neither.   
   
   
       47 . A method according to  claim 46 , wherein the method comprises:
 obtaining a list of non-authenticated IP addresses from a remote server; and   appending the list of non-authenticated IP addresses to the database of non-authenticated IP addresses.   
   
   
       48 . A method according to  claim 40 , wherein the content-provider server has a hostname and the method comprises:
 obtaining first data from the content-provider having the hostname;   resolving the IP address of the hostname;   obtaining second data from a content-provider having the resolved IP address;   comparing the first data and second data; and   providing an indication that the first data and second data are identical or non-identical.   
   
   
       49 . A method according to  claim 40 , wherein content-provider server has a URL and the fragment includes one or more URLs or portions of URLs associated with each IP address stored by the fragment, and the method comprises:
 comparing at least a portion of the URL of the content-provider server against the URLs or portions of URLs of the fragment that are associated with the IP address of the content-provider server; and   providing an indication that the IP address and the portion of the URL of the content-provider server is included in or excluded from the fragment.   
   
   
       50 . A client computer connectable to a content-provider server over a communications network, wherein the client computer is operable to:
 determine a domain name of the content-provider server;   obtain a fragment of a database of IP addresses, the fragment corresponding to the domain name of the content-provider server and storing one or more IP addresses associated with the domain name;   compare the IP address of the content-provider server against the IP addresses of the fragment; and   provide an indication that the IP address of the content-provider server is included or excluded from the IP addresses of the fragment.   
   
   
       51 . A client computer according to  claim 50 , wherein the client computer is operable to request data from the content-provider server and to obtain the fragment in response to the request for data from the content-provider server. 
   
   
       52 . A client computer according to  claim 50 , wherein the client computer is operable to:
 request data from the content-provider server; determine whether data from the content-provider server has previously been requested; and   to obtain the fragment if data from the content-provider has not previously been requested.   
   
   
       53 . A client computer according to  claim 50 , wherein the client computer is operable to:
 obtain data from the content-provider server that includes a link to a further content-provider server;   compare the IP address of the further content-provider server against the IP addresses of the fragment; and   provide an indication that the IP address of the further content-provider server is included or excluded from the received database of IP addresses.   
   
   
       54 . A security server connectable to a client computer over a communications network, the security server storing a database of IP addresses as a plurality of fragments, each fragment corresponding to a domain name and storing IP addresses associated with the domain name, and the security server is operable to receive a request from the client computer for a fragment, and to deliver the requested fragment to the client computer. 
   
   
       55 . A security server according to  claim 54 , wherein the security server is connectable to a content-provider server over the communications network and the security server is operable to:
 receive one or more IP addresses from the content-provider server; and   store the received IP addresses as a fragment, the fragment corresponding to a domain name of the content-provider server.   
   
   
       56 . A security server according to  claim 54 , wherein the security server stores a database of authenticated IP address as a plurality of fragments, each fragment corresponding to a domain name and storing authenticated IP addresses associated with the domain name, and a database of non-authenticated IP addresses, and the security server is operable to:
 receive a request from the client computer for a fragment of the database of authenticated IP addresses;   deliver the requested fragment to the client computer;   receive a request from the client computer for the database of non-authenticated IP addresses; and   deliver the database of non-authenticated IP addresses to the client computer.   
   
   
       57 . A security server according to  claim 54 , wherein the security server is operable to receive a request from the client computer that includes information identifying a domain name of a content-provider server, and to deliver to the client computer a fragment corresponding to the identified domain name.